This invention relates to machine tools and more particularly to machine tools having multiple spindles.
Machine tools with multiple spindles are used in assembly processes to tighten many fasteners at one time. When the torque requirement is low, i.e. less than 12 Nm, the tools are quite often ineffective. Under these conditions the tool will often under-tighten one or more of the fasteners. This leads to the inspector or the operator to use a separate tool to tighten the incorrect fasteners. In many instances, the manufacturer has resorted to using a single spindle nut runner in place of a multiple spindle tool. This solution results in a more time consuming operation.
It is an object of the present invention to provide an improved multiple spindle tool.
In one aspect of the present invention, a single motor is employed to drive a plurality of spindles. In another aspect of the present invention, a gear arrangement is placed between the motor and the spindles. In yet another aspect of the present invention, the gear arrangement is comprised of a central gear (sun gear) and three planet gears. In still another aspect of the present invention, the planet gears are fixed in a common carrier.
In yet still another aspect of the present invention, each of the spindles has an input shaft and an output shaft. In a further aspect of the present invention, an adjustable slip clutch is positioned between the input shaft and output shaft for each of the spindles. In a yet further aspect of the present invention, the gearing arrangement, input and output shafts, and the slip clutches are enclosed in a housing. In a still further aspect of the present invention, the output shaft of each spindle is supported in a bearing positioned in a lower cover of the housing.